diff --git a/jupyterhub/tests/test_api.py b/jupyterhub/tests/test_api.py
index defc5e28..b63489f9 100644
--- a/jupyterhub/tests/test_api.py
+++ b/jupyterhub/tests/test_api.py
@@ -8,9 +8,9 @@ import sys
 from unittest import mock
 from urllib.parse import urlparse, quote
 import uuid
+from async_generator import async_generator, yield_
 
 from pytest import mark
-
 from tornado import gen
 
 import jupyterhub
@@ -684,6 +684,161 @@ def test_slow_bad_spawn(app, no_patience, slow_bad_spawn):
     assert app.users.count_active_users()['pending'] == 0
 
 
+def next_event(it):
+    """read an event from an eventstream"""
+    while True:
+        try:
+            line = next(it)
+        except StopIteration:
+            return
+        if line.startswith('data:'):
+            return json.loads(line.split(':', 1)[1])
+
+
+@mark.gen_test
+def test_spawn_progress(request, app, no_patience, slow_spawn):
+    db = app.db
+    name = 'martin'
+    app_user = add_user(db, app=app, name=name)
+    r = yield api_request(app, 'users', name, 'server', method='post')
+    r.raise_for_status()
+    r = yield api_request(app, 'users', name, 'server/progress', stream=True)
+    r.raise_for_status()
+    request.addfinalizer(r.close)
+    ex = async_requests.executor
+    line_iter = iter(r.iter_lines(decode_unicode=True))
+    evt = yield ex.submit(next_event, line_iter)
+    assert evt == {
+        'progress': 0,
+        'message': 'Server requested',
+    }
+    evt = yield ex.submit(next_event, line_iter)
+    assert evt == {
+        'progress': 50,
+        'message': 'Spawning server...',
+    }
+    evt = yield ex.submit(next_event, line_iter)
+    url = app_user.url
+    assert evt == {
+        'progress': 100,
+        'message': 'Server ready at {}'.format(url),
+        'html_message': 'Server ready at <a href="{0}">{0}</a>'.format(url),
+        'url': url,
+        'ready': True,
+    }
+
+
+@mark.gen_test
+def test_spawn_progress_not_started(request, app):
+    db = app.db
+    name = 'nope'
+    app_user = add_user(db, app=app, name=name)
+    r = yield api_request(app, 'users', name, 'server', method='post')
+    r.raise_for_status()
+    r = yield api_request(app, 'users', name, 'server', method='delete')
+    r.raise_for_status()
+    r = yield api_request(app, 'users', name, 'server/progress')
+    assert r.status_code == 404
+
+
+@mark.gen_test
+def test_spawn_progress_not_found(request, app):
+    db = app.db
+    name = 'noserver'
+    r = yield api_request(app, 'users', 'nosuchuser', 'server/progress')
+    assert r.status_code == 404
+    app_user = add_user(db, app=app, name=name)
+    r = yield api_request(app, 'users', name, 'server/progress')
+    assert r.status_code == 404
+
+
+@mark.gen_test
+def test_spawn_progress_ready(request, app):
+    """Test progress API when spawner is already started
+
+    e.g. a race between requesting progress and progress already being complete
+    """
+    db = app.db
+    name = 'saga'
+    app_user = add_user(db, app=app, name=name)
+    r = yield api_request(app, 'users', name, 'server', method='post')
+    r.raise_for_status()
+    r = yield api_request(app, 'users', name, 'server/progress', stream=True)
+    r.raise_for_status()
+    request.addfinalizer(r.close)
+    ex = async_requests.executor
+    line_iter = iter(r.iter_lines(decode_unicode=True))
+    evt = yield ex.submit(next_event, line_iter)
+    assert evt['progress'] == 100
+    assert evt['ready']
+    assert evt['url'] == app_user.url
+
+
+@mark.gen_test
+def test_spawn_progress_bad(request, app, no_patience, bad_spawn):
+    """Test progress API when spawner is already started
+
+    e.g. a race between requesting progress and progress already being complete
+    """
+    db = app.db
+    name = 'simon'
+    app_user = add_user(db, app=app, name=name)
+    r = yield api_request(app, 'users', name, 'server', method='post')
+    assert r.status_code == 500
+    r = yield api_request(app, 'users', name, 'server/progress', stream=True)
+    r.raise_for_status()
+    request.addfinalizer(r.close)
+    ex = async_requests.executor
+    line_iter = iter(r.iter_lines(decode_unicode=True))
+    evt = yield ex.submit(next_event, line_iter)
+    assert evt == {
+        'progress': 100,
+        'failed': True,
+        'message': "Spawn failed: I don't work!",
+    }
+
+
+@mark.gen_test
+def test_spawn_progress_cutoff(request, app, no_patience, slow_spawn):
+    """Progress events stop when Spawner finishes
+
+    even if progress iterator is still going.
+    """
+
+    @async_generator
+    async def progress_forever():
+        for i in range(1, 10):
+            await yield_({
+                'progress': i,
+                'message': 'Stage %s' % i,
+            })
+            # wait a long time before the next event
+            await gen.sleep(10)
+
+    db = app.db
+    name = 'geddy'
+    app_user = add_user(db, app=app, name=name)
+    app_user.spawner.progress = progress_forever
+    app_user.spawner.delay = 1
+
+    r = yield api_request(app, 'users', name, 'server', method='post')
+    r.raise_for_status()
+    r = yield api_request(app, 'users', name, 'server/progress', stream=True)
+    r.raise_for_status()
+    request.addfinalizer(r.close)
+    ex = async_requests.executor
+    line_iter = iter(r.iter_lines(decode_unicode=True))
+    evt = yield ex.submit(next_event, line_iter)
+    assert evt['progress'] == 0
+    evt = yield ex.submit(next_event, line_iter)
+    assert evt == {
+        'progress': 1,
+        'message': 'Stage 1',
+    }
+    evt = yield ex.submit(next_event, line_iter)
+    assert evt['progress'] == 100
+
+
 @mark.gen_test
 def test_spawn_limit(app, no_patience, slow_spawn, request):
     db = app.db